As a structure of a semiconductor light emitting device such as an LED (light emitting diode), there is a structure in which, for example, a crystal layer formed on a substrate is joined to a conductive substrate and then the substrate is removed. In this structure, the light extraction efficiency can be increased by performing roughening processing on the surface of the crystal layer exposed by removing the substrate. There is also a structure in which no electrode is formed on the surface of a crystal layer serving as a light extraction surface and a p-side electrode and an n-side electrode are formed on the crystal surface on the opposite side to the surface from which a substrate has been removed. In such semiconductor light emitting devices, further improvement in the light extraction efficiency is required.